Traveling cylinder imprinter with wheel-centering means and cylinder-locking means for variable data input

ABSTRACT

A variable data imprinter for use in recording credit card sales transactions is provided having a plurality of indicia bearing toothed print wheels and a corresponding plurality of toothed racks for cooperation with the print wheels so that the print wheels are selectively indexible with respect to a printing position by movement of the respective racks. Control means are provided for centering the print wheels with respect to their printing position and for preventing actuation of a printing roller until such centering operation has been effected. The print wheel centering operation is effected by movement of a lever arm which carries a centering bar for engagement with stops formed on the toothed racks. Movement of the lever arm is also utilized to operate a locking mechanism which normally prevents actuation of the roller until the lever arm is operated.

Barbour United States Patent 1 1 1 1 June 19, 1973 TRAVELING CYLINDER IMPRINTER WITH WHEEL-CENTERING MEANS AND CYLINDER-LOCKING MEANS FOR VARIABLE DATA INPUT William P. Barbour, Alexandria, Va.

Inventor:

[73] Assignee: Control Data Corporation,

' Washington, DC.

[22] Filed: Apr. 29, 1971 211 7 Appl. No.: 138,730

[52] U.S. Cl. 101/45, 101/269 [51] B4lf 3/60 [58] Field of Search 101/19, 20, 45, 95, 101/269, 56

[56] References Cited I UNITED STATES PATENTS 3,138,091 6/l964 Maul 101/45 3,279,369 10/1966 Wight 101/269 3,322,062 5/1967 Maul 101/45 3,334,582 8/1967 Mahoney... 101/45 3,468,244 I 9/1969 Hu 101/45 X Maul 'et a1 101/269 X 3,515,060 6/1970 Barbour 101 /45 Primary ExaminerRobert E. Pulfrey Assistant ExaminerEdward M. Coven Attorney-Cushman, Darby & Cushman 57 ABSTRACT A variable data imprinter for use in recording credit card sales transactions is provided having a plurality of indicia bearing toothed print wheels and a corresponding plurality of toothed racks for cooperation with the print wheels so that the print wheels are selectively indexible with respect to a printing position by movement of the respective racks. Control means are provided for centering the print wheels with respect to their printing position and for preventing actuation of a printing roller until such centering operation has been effected. The print wheel centering operation is effected by movement of a lever arm which carries a centering bar for engagement with stops formed on the toothed racks. Movement of the lever arm is also utilized to operate a locking mechanism which normally prevents actuation of the roller until the lever arm is operated.

18 Claims, 11 Drawing Figures Patented Jun 19, 1973 5 Sheets-Sheet 1 INVENTOR. M4 .4 MW P5flfi8004 BY Mu. ,Mo? m 19 7' 0174 5 Y3 Patented June 19, 1973 3,739,716

5 Sheets-Sheet 3 INVENTOR Q M MW P51985001? ATTORNEYS Patented June 19, 1973 3,73,7R

5 Sheets-Sheet 6 ORNEYS Patented June 19, 1973 3,739,716

5 Sheets-Sheet 5 1N VENTOR M1 1 AQ/VPBfl/FBOI/A MWA ,MM

ATTORNEYS TRAVELING CYLINDER IMPRINTER WITH WHEEL-CENTERING MEANS AND CYLINDER-LOCKING MEANS FOR VARIABLE DATA INPUT BACKGROUND OF THE INVENTION The widespread use of credit cards having raised symbols in sales, banking and other transactions has resulted in a corresponding increase in the demand for a reliable printing device that is capable of recording the necessary information in clear, easily readable form on documents. Such printing machines which are often referred to as imprinters have been utilized to transfer information embossed on a plastic card as well as data relating to the particular transaction such as date, price, etc., on a documentwhich is subsequently relied upon as the record of the transaction, e.g., in the case of sales, for the purpose of billing the customer. The documents that are commonly used to record such transactions usually consist of a plurality of sheets containing one or more carbons to provide several copies of the transaction. Since it is highly desirable if not essential to obtain clear impressions on each of the copies of the documents, imprinters using a rolling platen have been resorted to for carrying out the printing operation.

The printing devices which are presently in common use generally consist of a flat surface on which is placed the credit card of the customer over which is positioned a sales document. A print head in the form ofa roller is then traversed over the document supporting surface to apply smooth, even pressure to the sales document so as to transfer a clear image of the symbols embossed on the credit card to the sales document. In some printing arrangements, variable data such as price and date information may be transferred to the sales document upon one traversal of the document by the printing head.

It has been found that the printing elements that sup ply the variable data such as the price are subject to substantially more wear than, for example, the embossed characters provided on a customers credit card. This is so obviously because in a retail sales outlet, the printing elements of an imprinter will be used in the course of a business day to record substantially more transactions than is the case with an individual customers credit card. Over one hundred repetitions per day is not unusual for such machines in busy gasoline stations and department stores for example. Where the entry of the variable data is by means of print wheels which are rotated to expose raised characters to the sales document, it has been found that in order to obtain clear impressions substantial pressure must be applied to these characters of the print wheels and as a result,a variation in theposition of the wheels with respect to the printing bed is likely to occur which is undesirable particularly where .it is necessary to obtain printing of a quality capable of cooperation with optical character reading devices.

Centering devices for the print wheels have been used to assure the proper positioning of the indicia once they have been selected prior to carrying out the printing stroke, and such centering devices are affected by wear throughout the course of the life of the machine.

While many imprinters render good quality print impressions when they are first placed in service, the print quality of such machines often becomes objectionably poor under sustained usage. Moreover, rough handling of the imprinters by indifferent personnel as well as variations in humidity, temperature or the like all adversely affect the quality of the impressions, frequently to an extent that renders the impressions useless for reading by optical reading equipment.

In large volume retail outlets wherein a large number.

of credit sales are transacted in a course of a day, many imprinters having means for entering and printing variable data such as the price on a sales document have generally lacked means for assuring that the correct entries will be made before the sales clerk actuates the printing roller. Errors sometimes occur where the price of the sales transaction varies from customer to customer, as for example in large department stores and incorrect entry of price information on sales documents can result in great customer dissatisfaction as well as losses to the retailer.

The printing machine of the present invention avoids the foregoing and other deficiencies as will be hereinafter set forth and will provide print quality of a high degree of excellence over long periods of time under the usual as well as often severe field conditions.

SUMMARY OF THE INVENTION The present invention provides an improved mechanism for selectively positioning data relative to a document supported on a printing bed over which a print roller is manually moved to press the document against the data that is presented. The print roller used is of the type disclosed in US. Pat. No. 3,538,848, entitled Latch Means For A Travelling Roller Platen On A Swingable Carriage granted Nov. 10, 1970 to the same inventor as the present invention. In the arrangement of the present invention, a plurality of print wheels are rotatably supported in a housing located beneath the printing bed. Each print wheel is formed with a plurality of raised printing indicia, each of which is located on the exterior of a tooth of the wheel. Each tooth of the wheel is spaced a predetermined arcuate distance from adjacent teeth so that, in effect, each printing wheel is adapted to function as its own toothed gear. The housing in which the printing wheels are supported extends generally transverse to the printing bed and also encloses a number of toothed racks corresponding to the number of print wheels-The racks are mounted for reciprocating movement transverse to the axis of a shaft on which the print wheels are supported and with the tooth of each rack respectively engaging the teeth of each print wheel so that movement of the racks will effect rotation of the wheels.

The bottom of each rack opposite the print wheel engaging teeth is provided with a plurality of downwardly facing V-shaped centering notches, each of the apices of which is located opposite a midpoint between adjacent teeth which engage and rotate the respective print wheel. A complementary shaped centering bar in the form of a knife edge is mounted on a movable arm beneath the racks so that the centering bar extends transversely across all of the racks. Spring means are provided for constantly urging the centering arm upwardly to maintain the centering bar in contact with the notches on the racks. The centering bar is provided with an apex which, as a result of the spring bias, will engage a notch positioned immediately above it and, as a result, will shift each rack so as to bring the respective indicia on the print wheels to a substantially precise printing position with respect to the printing bed. With the centering bar engaging the respective notches of the racks, the racks are effectively locked in position to prevent movement thereof by an operator. A lever arm is provided for manually disengaging the centering bar from the notches of the racks and which is conveniently located on the exterior of the housing. In addition to the aforementioned function of disengaging the centering bar from the racks, the lever arm also is used to operate a slip clutch arrangement which is provided to control the movement of a detent member located adjacent the rest position of the print roller. The detent operates to prevent movement of the print roller through its printing stroke until the lever arm has first moved the centering bar out of engagement with the notches of the racks and then returned to its initial position allowing the centering bar to again engage the notches of the racks and perform the print wheel cen tering function. Only after this sequence of steps will the detent arrangement permit an individual to move the print roller through its printing stroke.

With the foregoing arrangement, and as will be more fully described hereinafter, the possibility of an operator of the device entering incorrect data for a particular transaction by failing to change the data from a previous setting will be substantially minimized since the operator must first manipulate the lever arm which is positioned adjacent to the key means for moving the racks.

It is one of the objects of the present invention to provide an improved imprinter capable of supplying impressions of superior quality over long periods of use and under rugged conditions.

Another object of the invention is to provide a variable data imprinter that is relatively easy to operate and which is provided with means for minimizing the possibility of errors in registering correct data for a transaction.

A further object of the invention is to provide a variable data imprinter having adjustments for compensating for wear and which can be easily adjusted to maintain excellent quality print impressions.

Another object of the present invention resides in the provision of a control lever, the operation of which effects the centering of the print wheels with respect to the printing bed and also unlocks the printing roller subsequent to the centering operation.

These and other objects and attendant advantages will become apparent as further consideration is given to the following detailed description and accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in perspective of the variable data imprinter of the present invention;

FIG. 2 is a cross-sectional view taken along lines 2-2 of FIG. 1;

FIG. 3 is a cross-sectional view taken along lines 3-3 of FIG. 2;

FIG. 4 is an enlarged detailed view of the clutch arrangement of the present invention;

FIG. 5 is a view taken along lines 5-5 of FIG. 4;

FIG. 6 is a cross-sectional view taken along lines 6-6 of FIG. 2;

FIG. 7 is a view taken along lines 7--7 of FIG. 6;

FIGS. 8 and 9 are views similar to FIGS. 4 and 5 and illustrate an alternate embodiment of the clutch arrangement of the present invention;

FIG. 10 is a view in perspective of the cam means employed for adjusting the position of the centering bar; and

FIG. 11 is a detailed view illustrating the cooperation between the device of the present invention and a digital encoder.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, there is illustrated in FIG. 1 an embodiment of the variable data imprinter of the present invention generally designated at 10. The imprinter 10 consists chiefly of two parts; a rolling platen imprinter generally designated at 12, and a variable data input apparatus, generally designated at 14. As noted previously, the platen imprinter 12 is constructed substantially along the lines as that disclosed in the aforementioned US. Pat. No. 3,538,848. As illustrated in FIG. 1, the rolling platen imprinter 12 consists of a carriage 16 provided with a cover 18 shaped irregularly for comfort as a hand grip for the user of the imprinter. Carriage 16 is adapted to traverse a printing bed 20 through a rectilinear, imprint stroke towards the right as viewed in FIG. 1 and then returned to its rest position. Left and right tracks, one of which is shown at 22 are provided on either side of the printing bed 20 and in which are located a pair of rollers in each track, two of which are indicated at 24 in phantom lines. Each of the rollers is rotatably journaled on shafts mounted on the depending side flanges, one of which is indicated at 26. A hard, cylindrical printing roller is rotatably mounted on a shaft within cover 18 (FIG. 6). As is fully described in the aforementioned patent, the entire printing roller assembly is mounted for pivotal movement within the carriage between an imprint position during the printing stroke of the carriage 16 and a raised, nonimprint position during the carriage return stroke.

The printing bed itself is provided with card locators as at 28 and 30 as well as locators for a sales document as at 32 and 34. A permanently positioned embossed plate 36 (commonly referred to as a dealer plate) may be provided at any suitable place such as shown in FIG. 1, next to the adjustable calendar date wheels 38.

With the apparatus as thus far described, it has been the usual practice to first place a printing plate, referred to herein as a credit card, within the locators 28 and 30 and then to superimpose a multileaf sales document set thereon. The carriage 16 was then operated through its printing stroke to transfer the information from the customers credit card directly to the pages of the sales document via the transfer of carbon from the carbon sheets of the document set. Subsequently the clerk has been required to manually fill in the sales document with the particular information identifying the sales transaction such as, for example, price information, merchandise, etc. Such procedures are clearly undesirable and should be discouraged since the possibility of inaccuracies in transcribing such price information for the purposes of billing the customer are appreciable. Moreover, in view of the widespread use of credit cards to record credit sales transactions, the desirability of using optical character reading devices to scan an imprinted sales document has become apparent to business concerns handling a large volume of such documents.

The variable input apparatus 14 of the present invention is particularly adapted to cooperate with a rolling platen imprinter to obtain printed impressions on a sales document of sufficient quality to enable the impressions to be accurately scanned by optical character reading devices. As seen in FIG. 1, the apparatus 14 consists of a housing 40 which extends generally transverse to the printing bed and is positioned underneath of the rolling platen imprinter 12. The housing 40 is securely attached, e.g., bolted as at (FIGS. 1 and 6), to the underside of the printing bed 20 to assure that the printing wheels indicated at 42 will be accurately positioned vertically with respect to the surface of the printing bed 20.

The upwardly facing side 44 of the housing may be appropriately provided with a variety of indicia corresponding to the raised printing surfaces on the print wheels 42. As shown in FIG. 1, by way of example, numerical symbols have been provided but it will be understood that other types of indicia may be used. A plurality of slot-like channels, one of which is indicated at 46 are formed through the surface 44 and adjacent one end of each of the slots a window, one of which is indicated at 48 is provided for the purpose of clearly indieating to the user of the device precisely what symbol is being presented to the sales document by the printing wheels 42. The manually engageable portion 50 of a control lever projects through a slot 52 formed in side 54 of housing 40.

With reference now to FIG. 2, there is illustrated at 56 and 58 two of the racks which are mounted in housing 40. Each rack is provided with two longitudinally extending slots, one at the forward half as at 60 and the other on the rearward portion as at 62. Two shafts are provided in the housing 40, one at 64 which passes through the respective forward slots 60 and one at 66 which passes through the rearward slots 62. As shown in FIGS. 3 and 6, washers as at 68 and 70 are mounted on shafts 66 and 64 respectively between each rack.

The washers are constructed from material that is resistant to deformation resulting from temperature and humidity variations so as to maintain the racks in their spaced positions. Glass-filled acetal is one such material.

The rear end of each rack is provided with a prong 72 which extends upwardly through the respective channels 46. A plastic key 74 is frictionally attached to theextending portion of each prong to facilitate actuation of each rack.-An indicia bearing strip 76 is supported on a slotted channel 78 within housing 40 through which the respective prongs 72-extend so thatupon movement of each rack the indicia bearing strip will present a symbol in each window 48 corresponding to the symbol presented by the associated print wheel.

The top side of each rack on its forward portion is formed with a plurality of teeth as at 80 which interfit with the notches between the raised indicia on the associated print wheels as at 82. The print wheels themselves are mounted on shaft 84 and are freely rotatable thereon independently of one another in response to movement of the respective rack associated therewith.

On the bottom side of each rack opposite the teeth 80, a plurality of centering stops in the form of V- shaped notches as at 86 are provided. The apex 87 of each notch 86 is located directly opposite the midpoint between each of the gear teeth on the top side of each rack.

On the interior of the bottom wall 88 of the housing 40, a generally U-shaped yoke 90 is adjustably secured and which supports a centering arm 92 in the form of a flat plate which is pivotally mounted by means of a pair of apertured clips 93 on a shaft 94 which extends through the upwardly extending legs of the U-shaped yoke 90. A generally oval opening 96 is formed in the base of yoke 90 in which is disposed an eccentric cam member 98 (FIG. 10) which is secured to the wall by a nut and stud. By rotating the eccentric cam member 98 about a generally vertical axis, the yoke 90 may be translated rectilinearly to the left or right as viewed in FIG. 2 to effect a corresponding translation of the centering arm 92.

Centering arm 92 supports a centering bar 104 (FIGS. 2 and 5) in a manner enabling the bar to rock about an axis established by a pin 106 which extends parallel to arm 92. To accomplish this, a socket 100 is formedin arm 92 for receiving a ball 102 having pin 106 projecting therefrom and trapped by a bore in stud 108 which extends through slot 110 in arm 92, pin 106 is free to rotate in the bore stud 108. Washer plate 105 is provided to exert a small frictional drag on ball 102. Centering bar 104 is formed integrally with ball 102. A tightening nut 112 is threaded onto the other end of stud 108 (FIG. 2) so that the stud 108 may be held in slot 110.

With the foregoing arrangement, two adjustments of the centering bar 104 are possible, namely, centering bar 104 may be pivoted about a generally horizontal axis corresponding to the longitudinal axis of pin 106, and, by shifting stud 108 in slot 110, the centering bar 104 will be rotated about a generally perpendicular axis. As previously noted centering bar 104 may be shifted transversely of the racks upon rotation of the eccentric cam 98. To effect the foregoing adjustments, an aperture is provided beneath tightening nut 112 in the bottom wall 88 of the housing 40 and an aperture 115 is provided in centering arm 92 immediately above nut 1l4 which holds the flange on eccentric cam 98 in place.

FIG. 4 shows a spring 116 used in tension to maintain the centering bar 104 in engagement with the notches of the respective racks by resiliently lifting arm 92. One end of the spring 116 is secured to a hooklike member 118 which is nonrotatably carried on shaft 84. The other end of spring 1 16 is attached to the end of centering arm 92 remote from shaft 94. As illustrated in FIG.

5, control means in the form of a lever arm 120 is also pivotally mounted at one end on shaft 94 and extends the length of the housing 40 through slot 52 in side 54. Alug 122 extends outwardly from centering arm 92 into an aperture formed in the side of lever arm 120 so that when the lever arm is pivoted downwardly the centering arm 92 as well as the centering bar 104 connected thereto will also be pivoted downwardly to thus move the centering bar 104 out of contact with the notches on the racks to thus permit an operator of the printing device to shift the racks. The strength of spring 116 is great enough so that when the lever arm 120 is returned to its raised position, centering bar 104 will engage the notches of the racks with sufficient pressure to carry out the centering operation.

In FIG. 3 there is illustrated a clicker mechanism consisting of a housing 124 supporting pointed shafts 126 which are biased upwardly by springs 128. The tips of the shafts engage small notches 130 formed on the lower edge of each of the racks (FIG. 2) In an alternate embodiment, the clicker mechanism is replaced by a plurality of digital encoding devices one of which is shown at 132 in FIG. 11, so that the information presented by the print wheel corresponding to a particular longitudinal shifting of an associated rack will be measured by an encoder which in turn produces an electrical signal that is transmitted by the conductors in cable 134 to data processing equipment (not shown). The notches 133 are formed to correspond to the centered position of each character on the associated wheel. A switch 200 (FIG. 7) is mounted on printing bed in the path of carriage 16 and connected by cable 202 to encoders 132, so that the output of the digital encoders will be transmitted to the data processing equipment only upon completion of the printing stroke of the carriage l6, i.e., when switch 200 is actuated by being engaged by the carriage.

FIGS. 6 and 7 show the arrangement of elements to prevent movement of the carriage containing printing roller 136, prior to operation of the print wheel cnetering bar 104. As shown in FIG. 6, the hook-like member 118 is part of a strut element 138 the bottom end of which engages shaft 64. A micrometer adjustment device 140 is provided between the outside surface of the outer printing wheel and the inside surface of the housing 40 on shaft 84. The notches 142 in member 144 differ in depth by only a very small degree, for example, on the order of 0.01 of an inch between each notch. The adjustment is obtained by rotating member 146 relative to member 144 to bring its tooth 148 into engagement with the notch having the appropriate depth for positioning the print wheels with respect to the printing bed 20 longitudinally on shaft 84.

The printing roller release mechanism 150 consists of a catch arm 152 which is pivotally mounted on a block 154 which in turn is rigidly secured to a shaft 156. One end of the shaft 156 is rotatably secured in a wall 158 which depends from the printing bed 20 adjacent an aperture 160 formed therein and up through which the catch arm 152 extends. The other end of shaft 156 is rotatably journaled in a socket formed in the end of shaft 84 as illustrated in FIG. 7. A clutch rod support arm 162 is rotatably mounted on shaft 84 as by collar 164 while the other end of the support arm 162 is rigidly secured to shaft 156 or it may form a part of shaft 156 to be rotatable therewith. A clutch rod 166 is rotatably secured in collar 164 of the support arm 162 on one side of shaft 84 (see FIG. 4). As illustrated in FIG. 5, the clutch rod '166 depends from the collar 164 downwardly through .an aperture 168 formed in a plate member 170 which is secured to the top side of lever arm 120. A spring wire 172 is secured to plate 170 so as to constantly press against clutch rod 166. A pin is provided in support arm 162 on the opposite side of shaft 84 from the side that the clutch rod 166 is located. The end of the pin extending above support arm 162 will abut a horizontally disposed flange 176 extending outwardly from the housing 40 so that when lever arm 120 is provided downwardly, pin 174 will engage the underside of flange 176 to prevent rotation of shaft 156 and the spring wire 172 will slip on clutch rod 166 since the clutch rod is prevented from moving downwardly therewith. However, when lever arm is returned to its raised position, clutch rod 166 will move upwardly therewith to effect rotation of shaft 156 about its longitudinal axis whereby catch arm 152 will be rotated out of the path of abutment surface 178 on the carriage 16 thus permitting movement of the carriage 16 through its printing stroke across printing bed 20.

The carriage 16 is provided with a trailing cam arm 180 which is so positioned (FIG. 7) that as the carriage 16 passes over aperture 160, cam arm 180 will engage the pivoted catch arm 152 to rotate the arm 152 back to its upright position as illustrated in FIG. 6. When the carriage 16 is returned to its rest position as shown in FIG. 6, the catch arm 152 will be pivoted downwardly upon contact with the rear edge of carriage 16 about axis 182 permitting the carriage to ride over the catch arm 152. A spring wire 184 is provided to resiliently urge the catch arm upwardly through aperture 160. It should be noted that the rotation of the arm 152 by virtue of its contact with cam arm 180 will be effective to rotate shaft 156 and to return clutch rod 166 to the position illustrated in FIG. 6.

With the foregoing arrangement, it will be understood that movement of the carriage 16 through a printing stroke can only be effected after the lever arm 120 has been pivoted downwardly and returned to its rest position. As previously noted, pivoting the lever arm 120 downwardly unlocks the racks thus permitting entry of data by rotation of the print wheels and the returning of the lever arm 120 to its rest position carries out the centering operation of the centering bar 104.

In FIGS. 8 and 9, there is illustrated an alternate embodiment of the printing device of the present invention wherein portion 186 which corresponds to plate 170 in the previous embodiment is formed integrally on a separate arm 188 one end of which is secured in a U- shaped yoke member 190. The depending legs of the yoke 190 are rotatably mounted on shaft 94 as is plate 92 and lever arm 120'. Arm 188 extends immediately above lever arm 120 and the two arms are separated by an adjustable screw 192 which extends through a threaded bore in arm 188. A separate bar element 194 is secured in portion 186 to engage the notch on the un- I derside of the adjacent toothed rack 196 next to the notch engaged by centering bar 104. Clutch rod 166 together with wire spring 172 are disposed as in the previous embodiment and carry out the same functions as previously described with the following differences. When arm 120' is pivoted downwardly, arm 188 will remain up and bar element 194 will remain in engagement with a notch of rack 196 due to the frictional engagement of spring 172 with clutch rod 166. In this embodiment, rack 196 may be associated with a print wheel that carries symbols used for distinguishing between credit cards issued by different concerns. Since spring 172 is substantially weaker than spring 116, bar element 194 will be pivoted downwardly in response to movement of rack 196. Movement of rack 196 will actuate the slip clutch arrangement so that when lever arm 120' is returned to its rest position arm 188 will also be moved upwardly to cause pivoting of shaft 156 to thus move catch arm 152 out of the path of the carriage 16 as previously described. With this arrangement, a sales clerk will be unable to move carriage 16 through a printing stroke until the proper credit card identifying symbol has been first positioned with respect to the printing bed 20 by movement of rack 196. In effect, the notches 198 on the underside of rack 196 function as cam surfaces which overcome the relatively small spring force of spring 172 to effect the downward pivoting of arm 188 and the corresponding slipping of spring 172 on clutch rod 166. 7

From the foregoing description, it can be seen that the present invention provides a printing device capable of providing printed impressions of excellent quality and which can be easily adjusted to maintain the high quality of the impressions over a long period of use. Additionally, the present invention provides means for reducing the possibility of error in entering data onto a sales document by requiring the manual manipulation of a control lever before a succeeding printing stroke may be effected.

While the invention has been particularly shown and described with reference to the foregoing preferred embodiments thereof, it will be understood by those skilled in the art that other changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

l. A variable data printing machine comprising:

a housing including a document supporting surface,

a printing member mounted for reciprocal motion relative to said document supporting surface and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said surface, variable data input means for selectively positioning data relative to said document supporting surface including a plurality of rotatably and coaxially mounted toothed wheels, each having raised characters for imparting impressions to a document interposed on said document supporting surface between said characters and said roller of said printing member, each of said characters being located on the periphery of a tooth of each wheel so that, upon rotation of a wheel through a predetermined angle, a selected character on a said wheel will be moved to a printing position with respect to said documentsupporting surface, and a plurality of toothed racks slidably mounted in said housing with teeth of each of said racks engaging teeth of each of said wheels so that displacement of an individual rack will effect rotation of an associated wheel,

control means supported by said housing including a first and a second lever arm, said lever arms being mounted in said housing for pivotal movement about a common axis between first and second positions respectively, said first lever arm having stop means carried thereon for cooperating with at least one of said racks, said second lever arm having centering means carried thereon for centering selected characters on said wheels with respect to said printing position, said centering means of said second lever arm being operable to center said respective characters when said second lever arm is pivoted from said first to said second and back to said first position respectively,

said control means further including locking means movable between a first position wherein movement of said printing member is prevented and a second position wherein movement of said printing member is permitted, said locking means being moved from said first to said second position in response to pivotal movement only of said first lever arm from said second position thereof to said first position. i

2. The printing machine as claimed in claim 1 wherein said locking means comprises a detent element mounted on a shaft, said shaft being mounted for rotation about its longitudinal axis in said housing so that rotation of said shaft will effect movement of said element from said first position to said second position, said shaft having clutch means mounted thereon connected to said first lever arm whereby movement of said first lever arm from said second position to said first position will be transmitted through said clutch means to effect rotation of said shaft.

3. The printing machine as claimed in claim 2 wherein said clutch means comprises a support arm rigidly attached to said shaft and having abutment means for preventing rotation of said shaft in one direction, a clutch rod pivotally attached at one end to said support arm at a radial distance from said shaft and slipably attached adjacent its other end to said first lever arm such that during movement of said first lever arm from said first position to said second position, said abutment means will prevent rotation of said shaft and movement of said clutch rod and, during movement of said first lever arm from said second position to said first position, said clutch rod will transmit the motion of said first lever arm to said support arm to effect rotation of said shaft.

4. The printing machine as claimed in claim 3 wherein spring means are provided on said first lever arm for resiliently engaging said clutch rod and said first and second lever arms are mounted to extend in substantially the same vertical plane, and spacer means are provided between said lever arms the strength of said spring-means being such that, when said second lever arm is pivoted from said first to said second position, said first lever arm will remain in its said first position, and when both of said lever arms are in their respective second positions, movement of said second lever arm to its said first position will effect movement of said first lever arm to its said first position.

5. The printing machine as claimed in claim 4 wherein said spacer means comprises an adjustable screw.

6. A variable data printing machine comprising:

a housing including a document supporting surface,

' a printing member mounted for reciprocal motion relative to said document supporting surface'and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said surface,

variable data input means for selectively positioning data relative to said document supporting surface to be imprinted on a document, said variable data input means including a plurality of rotatably and coaxially mounted toothed wheels, each having raised characters for imparting impressions to a document on said document supporting surface between said characters and said roller of said printing member, each of said characters being located on the periphery of a tooth of each wheel so that, upon rotation of a wheel through a predetermined angle, a selected character on a said wheel will be moved to a printing position with respect to said document supporting surface, said teeth being circumferentially spaced from each other to provide peripherally opening recesses between said teeth, a plurality of toothed racks slidably mounted in said housing with teeth of each of said racks engaging said recesses between teeth of each of said wheels so that displacement of an individual rack will effect rotation of an associated wheel,

control means supported by said housing and movable from one operative position to another position wherein data is selectively positionable by said variable data input means while movement of said printing member is prevented and to said one operative position from said other position wherein said printing member is movable through a printing stroke while positioning of data by said variable data input means is prevented,

means for centering said selected characters on said wheels with respect to said printing position including a series of stops on each of said racks, each stop having a center corresponding to the centered printing position of each character on each of said wheels, and a member connected to said movable control means and movable into engagement with a said center of said stops on each of said racks when said control means is moved from said other position to said one position whereby each of said racks will be moved to effect a corresponding rotation of each of said wheels to center said selected characters on said wheels in said printing position, said member being movable out of engagement with said stops when said control means is moved from said one position to said other position.

7. The printing machine as claimed in claim 6 wherein each of said toothed racks is provided with a plurality of indicating stops each having centers corresponding to the centered printing position of said characters and a plurality of digital encoders are provided, one for each rack, for producing an output correspond ing to the character presented for printing on each wheel, said printing machine having means for transmitting the output of said encoders to data processing equipment.

8. The printing machine as claimed in claim 6 wherein means are provided for biasing said control means toward said one position.

9. The printing machine as claimed in claim 6 wherein said control means includes means which retain said variable data input means in a fixed position in said one posltion and release the latter when said control means are moved to said another position.

10. The printing machine as claimed in claim 9 wherein said control means include a manually operable lever and resilient means for retaining said lever in said one position.

11. A variable data printing machine comprising,

a housing including a document supporting surface,

a printing member mounted for reciprocal motion relative to said document supporting surface and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said sufface,

variable data input means for selectively positioning data relative to said document supporting surface to be imprinted on a document, said variable data input means comprising a plurality of rotatably and coaxially mounted toothed wheels, each having raised characters for imparting impressions to a document interposed on said document supporting surface between said characters and said roller of said printing member, each of said characters being located on the periphery of a tooth of each wheel so that, upon rotation of a wheel through a predetermined angle, a selected character on a said wheel will be moved to a printing position with respect to said document supporting surface, said teeth being circumferentially spaced from each other to provide peripherally opening recesses between said teeth, plurality of toothed racks slidably mounted in said housing with teeth of each of said racks engaging said recesses between the teeth of each of said wheels so that displacement of an individual rack will effect rotation of an associated wheel, control means supported by said housing and movable from one operative position to another position wherein data is selectively positionable by said variable data input means while movement of said printing member is prevented and to said one operative position from said other position wherein said printing member is movable through a printing stroke while positioning of data by said variable data input means is prevented,

means for centering said selected characters on said wheels with respect to said printing position,

said character centering means comprising a knife edge connected to said movable control means and a series of stops on each of said racks, each stop having a center corresponding to said centered printing position of each character on each of said wheels, said knife edge being movable into engagement with said center of a said stop on each of said racks when said control means is moved from said other position to said one position whereby each of said racks will be moved to effect a corresponding rotation of each of said wheels to center said selected characters on said wheels in said printing position.

12. The printing machine as claimed in claim 11 including spring means for urging said control means to said one position of sufficient magnitude to operate said character centering means as said control means is urged into said one position.

13. The printing machine as claimed in claim 11 wherein each of said toothed racks is provided with a plurality of indicating stops each having centers corresponding to the centered printing position of said characters and a plurality of digital encoders are provided, one for each rack, for producing an output corresponding to the character presented for printing on each wheel, said printing machine having means for transmitting the output of said encoders to data processing equipment.

14. The printing machine as claimed in claim 13 wherein said means for transmitting the output of said digital encoders comprises a switch actuated in response to completion of the printing stroke of said printing member.

15. A variable data printing machine comprising:

a housing including a document supporting surface,

a printing member mounted for reciprocal motion relative to said document supporting surface and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said surface,

variable data input means for selectively positioning data relative to said document supporting surface to be imprinted on a document, and

control means supported by said housing and movable from one operative position to another position wherein data is selectively positionable by said variable data input means while movement of said printing member is prevented and to said one operative position from said other position wherein said printing member is movable through a printing stroke while positioning of data by said variable data input means is prevented,

said control means including locking means movable between a first position wherein movement of said printing member is prevented and a second position wherein movement of said printing member is permitted, said locking means being moved from said first position to said second position as said control means is moved from said other position to said one position,

said locking means comprising a detent element mounted on a shaft, said shaft being mounted for rotation about its longitudinal axis in said housing so that rotation of said shaft will effect movement 30 of said detent element from said first position wherein said element will intersect a portion of said printing member to said second position, wherein said element is out of the path of said portion said shaft having clutch means mounted thereon connected to said control means whereby movement of said control means only from said other position to said one position will be transmitted through said clutch means to effect rotation of said shaft.

16. The printing machine as claimed in claim 15 wherein said clutch means comprises a support arm rigidly attached to said shaft and having abutment means for preventing rotation of said shaft in one direction, a clutch rod pivotally attached at one end to said support arm at a radial distance from said shaft and slipably attached adjacent its other end to said control means such that during movement of said control means from said one to said other position, said abutment means will prevent movement of said clutch rod and, during movement of said control means from said other position to said one position, said clutch rod will transmit the motion of said control means to said support arm to effect rotation of said shaft.

17. The printing machine as claimed in claim 15 wherein resetting means are provided for moving said detent element from said second position to said first position.

18. The printing machine as claimed in claim 17 wherein said resetting means comprises a cam arm mounted on said printing member which engages said detent element upon movement of said printing member through a printing stroke, said printing member having a cam surface, said detent element being resiliently pivotable in one direction about an axis that extends generally perpendicularly to the longitudinal axis of said shaft so that, upon completionof a printing stroke, said cam surface on said printing member will contact said detent element to pivot said element out of the path of said printing member. 

1. A variable data printing machine comprising: a housing including a document supporting surface, a printing member mounted for reciprocal motion relative to said document supporting surface and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said surface, variable data input means for selectively positioning data relative to said document supporting surface including a plurality of rotatably and coaxially mounted toothed wheels, each having raised characters for imparting impressions to a document interposed on said document supporting surface between said characters and said roller of said printing member, each of said characters being located on the periphery of a tooth of each wheel so that, upon rotation of a wheel through a predetermined angle, a selected character on a said wheel will be moved to a printing position with respect to said document supporting surface, and a plurality of toothed racks slidably mounted in said housing with teeth of each of said racks engaging teeth of each of said wheels so that displacement of an individual rack will effect rotation of an associated wheel, control means supported by said housing including a first and a second lever arm, said lever arms being mounted in said housing for pivotal movement about a common axis between first and second positions respectively, said first lever arm having stop means carried thereon for cooperating with at least one of said racks, said second lever arm haviNg centering means carried thereon for centering selected characters on said wheels with respect to said printing position, said centering means of said second lever arm being operable to center said respective characters when said second lever arm is pivoted from said first to said second and back to said first position respectively, said control means further including locking means movable between a first position wherein movement of said printing member is prevented and a second position wherein movement of said printing member is permitted, said locking means being moved from said first to said second position in response to pivotal movement only of said first lever arm from said second position thereof to said first position.
 2. The printing machine as claimed in claim 1 wherein said locking means comprises a detent element mounted on a shaft, said shaft being mounted for rotation about its longitudinal axis in said housing so that rotation of said shaft will effect movement of said element from said first position to said second position, said shaft having clutch means mounted thereon connected to said first lever arm whereby movement of said first lever arm from said second position to said first position will be transmitted through said clutch means to effect rotation of said shaft.
 3. The printing machine as claimed in claim 2 wherein said clutch means comprises a support arm rigidly attached to said shaft and having abutment means for preventing rotation of said shaft in one direction, a clutch rod pivotally attached at one end to said support arm at a radial distance from said shaft and slipably attached adjacent its other end to said first lever arm such that during movement of said first lever arm from said first position to said second position, said abutment means will prevent rotation of said shaft and movement of said clutch rod and, during movement of said first lever arm from said second position to said first position, said clutch rod will transmit the motion of said first lever arm to said support arm to effect rotation of said shaft.
 4. The printing machine as claimed in claim 3 wherein spring means are provided on said first lever arm for resiliently engaging said clutch rod and said first and second lever arms are mounted to extend in substantially the same vertical plane, and spacer means are provided between said lever arms the strength of said spring means being such that, when said second lever arm is pivoted from said first to said second position, said first lever arm will remain in its said first position, and when both of said lever arms are in their respective second positions, movement of said second lever arm to its said first position will effect movement of said first lever arm to its said first position.
 5. The printing machine as claimed in claim 4 wherein said spacer means comprises an adjustable screw.
 6. A variable data printing machine comprising: a housing including a document supporting surface, a printing member mounted for reciprocal motion relative to said document supporting surface and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said surface, variable data input means for selectively positioning data relative to said document supporting surface to be imprinted on a document, said variable data input means including a plurality of rotatably and coaxially mounted toothed wheels, each having raised characters for imparting impressions to a document on said document supporting surface between said characters and said roller of said printing member, each of said characters being located on the periphery of a tooth of each wheel so that, upon rotation of a wheel through a predetermined angle, a selected character on a said wheel will be moved to a printing position with respect to said document supporting surface, said teeth being circumferentially spaced from each other to provide peripherally opening recesses between said teeth, A plurality of toothed racks slidably mounted in said housing with teeth of each of said racks engaging said recesses between teeth of each of said wheels so that displacement of an individual rack will effect rotation of an associated wheel, control means supported by said housing and movable from one operative position to another position wherein data is selectively positionable by said variable data input means while movement of said printing member is prevented and to said one operative position from said other position wherein said printing member is movable through a printing stroke while positioning of data by said variable data input means is prevented, means for centering said selected characters on said wheels with respect to said printing position including a series of stops on each of said racks, each stop having a center corresponding to the centered printing position of each character on each of said wheels, and a member connected to said movable control means and movable into engagement with a said center of said stops on each of said racks when said control means is moved from said other position to said one position whereby each of said racks will be moved to effect a corresponding rotation of each of said wheels to center said selected characters on said wheels in said printing position, said member being movable out of engagement with said stops when said control means is moved from said one position to said other position.
 7. The printing machine as claimed in claim 6 wherein each of said toothed racks is provided with a plurality of indicating stops each having centers corresponding to the centered printing position of said characters and a plurality of digital encoders are provided, one for each rack, for producing an output corresponding to the character presented for printing on each wheel, said printing machine having means for transmitting the output of said encoders to data processing equipment.
 8. The printing machine as claimed in claim 6 wherein means are provided for biasing said control means toward said one position.
 9. The printing machine as claimed in claim 6 wherein said control means includes means which retain said variable data input means in a fixed position in said one posltion and release the latter when said control means are moved to said another position.
 10. The printing machine as claimed in claim 9 wherein said control means include a manually operable lever and resilient means for retaining said lever in said one position.
 11. A variable data printing machine comprising, a housing including a document supporting surface, a printing member mounted for reciprocal motion relative to said document supporting surface and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said surface, variable data input means for selectively positioning data relative to said document supporting surface to be imprinted on a document, said variable data input means comprising a plurality of rotatably and coaxially mounted toothed wheels, each having raised characters for imparting impressions to a document interposed on said document supporting surface between said characters and said roller of said printing member, each of said characters being located on the periphery of a tooth of each wheel so that, upon rotation of a wheel through a predetermined angle, a selected character on a said wheel will be moved to a printing position with respect to said document supporting surface, said teeth being circumferentially spaced from each other to provide peripherally opening recesses between said teeth, a plurality of toothed racks slidably mounted in said housing with teeth of each of said racks engaging said recesses between the teeth of each of said wheels so that displacement of an individual rack will effect rotation of an associated wheel, control means supported by said housing and movable from one operative position to another positiOn wherein data is selectively positionable by said variable data input means while movement of said printing member is prevented and to said one operative position from said other position wherein said printing member is movable through a printing stroke while positioning of data by said variable data input means is prevented, means for centering said selected characters on said wheels with respect to said printing position, said character centering means comprising a knife edge connected to said movable control means and a series of stops on each of said racks, each stop having a center corresponding to said centered printing position of each character on each of said wheels, said knife edge being movable into engagement with said center of a said stop on each of said racks when said control means is moved from said other position to said one position whereby each of said racks will be moved to effect a corresponding rotation of each of said wheels to center said selected characters on said wheels in said printing position.
 12. The printing machine as claimed in claim 11 including spring means for urging said control means to said one position of sufficient magnitude to operate said character centering means as said control means is urged into said one position.
 13. The printing machine as claimed in claim 11 wherein each of said toothed racks is provided with a plurality of indicating stops each having centers corresponding to the centered printing position of said characters and a plurality of digital encoders are provided, one for each rack, for producing an output corresponding to the character presented for printing on each wheel, said printing machine having means for transmitting the output of said encoders to data processing equipment.
 14. The printing machine as claimed in claim 13 wherein said means for transmitting the output of said digital encoders comprises a switch actuated in response to completion of the printing stroke of said printing member.
 15. A variable data printing machine comprising: a housing including a document supporting surface, a printing member mounted for reciprocal motion relative to said document supporting surface and including a roller movable with said member through a printing stroke for imprinting data on a document supported on said surface, variable data input means for selectively positioning data relative to said document supporting surface to be imprinted on a document, and control means supported by said housing and movable from one operative position to another position wherein data is selectively positionable by said variable data input means while movement of said printing member is prevented and to said one operative position from said other position wherein said printing member is movable through a printing stroke while positioning of data by said variable data input means is prevented, said control means including locking means movable between a first position wherein movement of said printing member is prevented and a second position wherein movement of said printing member is permitted, said locking means being moved from said first position to said second position as said control means is moved from said other position to said one position, said locking means comprising a detent element mounted on a shaft, said shaft being mounted for rotation about its longitudinal axis in said housing so that rotation of said shaft will effect movement of said detent element from said first position wherein said element will intersect a portion of said printing member to said second position, wherein said element is out of the path of said portion said shaft having clutch means mounted thereon connected to said control means whereby movement of said control means only from said other position to said one position will be transmitted through said clutch means to effect rotation of said shaft.
 16. The printing machine as claimed in claim 15 wherein said clutch means comprises a suPport arm rigidly attached to said shaft and having abutment means for preventing rotation of said shaft in one direction, a clutch rod pivotally attached at one end to said support arm at a radial distance from said shaft and slipably attached adjacent its other end to said control means such that during movement of said control means from said one to said other position, said abutment means will prevent movement of said clutch rod and, during movement of said control means from said other position to said one position, said clutch rod will transmit the motion of said control means to said support arm to effect rotation of said shaft.
 17. The printing machine as claimed in claim 15 wherein resetting means are provided for moving said detent element from said second position to said first position.
 18. The printing machine as claimed in claim 17 wherein said resetting means comprises a cam arm mounted on said printing member which engages said detent element upon movement of said printing member through a printing stroke, said printing member having a cam surface, said detent element being resiliently pivotable in one direction about an axis that extends generally perpendicularly to the longitudinal axis of said shaft so that, upon completion of a printing stroke, said cam surface on said printing member will contact said detent element to pivot said element out of the path of said printing member. 